class_docstr: This class implements a model-specific automatic speech recognizer using the end-to-end speech recognizer
  DeepSpeech and PyTorch. It supports both version 2 and version 3 of DeepSpeech models as released at
  https://github.com/SeanNaren/deepspeech.pytorch.
  
  | Paper link: https://arxiv.org/abs/1512.02595
docstr: Return a string specifying a pure or mixed precision optimization level.
  
  :return: A string specifying a pure or mixed precision optimization level. Possible
           values are `O0`, `O1`, `O2`, and `O3`.
docstr_tok: ["Return","a","string","specifying","a","pure","or","mixed","precision","optimization","level",".",":","return",":","A","string","specifying","a","pure","or","mixed","precision","optimization","level",".","Possible","values","are","`","O0","`",",","`","O1","`",",","`","O2","`",",","and","`","O3","`","."]
code: def opt_level(self) -> str:
      """
      Return a string specifying a pure or mixed precision optimization level.
  
      :return: A string specifying a pure or mixed precision optimization level. Possible
               values are `O0`, `O1`, `O2`, and `O3`.
      """
      return self._opt_level
  
imports: import logging
  from typing import TYPE_CHECKING, List, Optional, Tuple, Union
  from pkg_resources import packaging
  import numpy
  from art import config
  from art.estimators.pytorch import PyTorchEstimator
  from art.estimators.speech_recognition.speech_recognizer import SpeechRecognizerMixin, PytorchSpeechRecognizerMixin
  from art.utils import get_file
label_desc: Use image node_id 15 for calling the PyTorchDeepSpeech obj's underlying member method code with example usage: obj.opt_level() and returns: self